Tutorial 04 for Arduino: Analog Inputs

New Episodes each Monday!

You can download the parts list, code, and schematics from this episode on my website:
http://jeremyblum.com/2011/01/24/arduino-tutorial-4-analog-inputs

Watch my TechBits Episode on Analog and Digital Signals: http://www.youtube.com/watch?v=Z3rsO912e3I

Submit your arduino project to element14's arduino contest for a chance to win a soldering station: http://www.youtube.com/watch?v=P5QpyIaycFo

This tutorial series is sponsored by element14. Check out their arduino group!
http://www.element-14.com/community/groups/arduino

Follow me on twitter: http://www.twitter.com/sciguy14

Category:

Science & Technology

Tags:

• arduino
• analog
• digital
• inputs
• reference
• voltage
• element14
• tutorial
• jeremy
• blum
• uno
• thermistor
• photoresistor
• IR
• distance
• sensor
• nightlight
• emergency
• light
• variable
• bits
• resolution
• ADC
• DAC

[WebDesigneri]

Hi! I have a variable resistor that can be set from 3.34 to 8.72 kohms. What's the best way to read the position of the variable resistor with an arduino and get the best resolution? The variable resistor has only 2 pins, so it doesn't work like a potentiometer.

[sciguy14]

@WebDesigneri If it only have two pins, how is it being varied? You can set it up in a voltage divder circuit with a fixed value resistor, and use the output voltage to determine the value of your variable resistor.

[Bryan7346]

I'm wondering if anyone on here could take a look at a few lines of code that I have written. I am trying to just make sure a small video camera stay on and stay recording, I am going to put it in a weather balloon. I believe it to be very simple code (to someone who know what theyre doing) but I have had some trouble with the REC button working. I have sent Jeremy Blum a msg directly via FB but he never responded. Please respond to this post if ur interested or email bryan246@gmail.com thanx

[sciguy14]

@Bryan7346 I never received a facebook message from you. Did you send it to the right Jeremy Blum? Use the contact form on my website.

[mudithead]

Hey, question- i have infrared sensor and everything but the the JST connector which connects the sensor to the breadboard is actually aluminium( that reddish- brownish fiber like thing) and not copper. Will that make any difference? Help

[sciguy14]

@mudithead no

[hullj15]

i have an arduino mega 2560 and i just got the arduino coding software so i try an exmple code but i couldnt upload it to my arduino the error message was somthing onlong the lines of serial port "com1"not found did you select the right one from tools>serial port menu? but for some reason in the tools menu the serial port button is faded out and i can acess it for some reason does any one know why and/or how to sort this problem? many thanks to anyone who can help.

[fabse64]

But I've got a question: On the schematics you show, anything that's not connected to something goes to ground, which is minus, is that right? That means we're basically only working with plus, right?

[fabse64]

Finally a channel it's worth subbing to. Thanks for your tutorials!

[davademon]

i made the led nightlight but i'm still afraid of monsters hiding in my closet. plzhlpthx

[WebDesigneri]

@sciguy14 The resistance varies when the actuator arm moves, so the position of the arm could be determined. So one wire is left. I assumed this would be the output from the potentiometer, but I don't get a voltage however I wire it (maybe it's broken?). I tried the voltage divider circuit with a fixed value resistor already, but didn't get that good of a resolution on the Arduino. What would be the best value for the fixed value resistor for this to work? Thanks for your help.

[WebDesigneri]

@sciguy14 The device I'm working with is actually a cruise control actuator. It has some kind of a potentiometer / variable resistor in it, but I can't get the output voltage of the pot from any wire that's coming out of the device. There are 7 wires total. Two are for controlling the motor in the actuator, 2 are for a solenoid that locks the actuator arm and I can read a varying resistance value between 2 wires.

[Rannyfash]

GLADOS!!!!!

[whilmer27]

HI SIR!!!

can you make a tutorial about RFID and adruino,. and aslo FINGER PRINT SCANNER and adruino., thanks in advance.,

[dubhealedlouiedawg]

Did you build the yellow robotic arm? or did you buy it anywhere? If yes to the latter, where can I get one?

[mehdiway]

Beautiful !!